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re-statement specifying what are included in the Conservation of Energy, and what are included in a Conservation of Force, and what is the distinction between the two classes. Within the class of the Conservation of Energy the distinction drawn between Energy of Position and Energy of Actual Motion was examined and criticised. A question was raised as to the Place of Feeling and Will in relation to the Forces of Nature, and more particularly affecting the constant quantity of Energy.
SIXTH ORDINARY MEETING.
ROYAL INSTITUTION, January 9th, 1882.
EDWARD DAVIES, F.C.S., F.I.C., PRESIDENT, in the Chair.
Captain Stubbs, R.N., and Mr. Phineas A. Benas were elected Ordinary Members.
Mr. JOSIAH MARPLES read a Note on the "Historical Errors in Mr. Swinburne's Poem, Mary Queen of Scots." *
Mr. CLEMENTS R. MARKHAM, C.B., F.R.S., Secretary of the Royal Geographical Society, then read a paper on "The Training of Sailors and Explorers.” †
SEVENTH ORDINARY MEETING.
ROYAL INSTITUTION, January 23rd, 1882.
EDWARD DAVIES, F.C.S., F.I.C., PRESIDENT, in the Chair.
Messrs. R. J. Tilson, Granville Sharpe, F.C.S., George Tate, Ph.D., F.G.S., F.C.S., and Heinrich Marcus were elected Ordinary Members.
The following communication was read:
NOTES ON THE ABNORMALLY HIGH BAROMETRIC PRESSURE RECORDED DURING JANUARY, 1882.
BY ARTHUR B. NEVINS, F.R.A.S., ASSOCIATE.
DURING the past fortnight meteorological phenomena have been observed sufficiently exceptional in their character to be worthy of notice.
Since the 14th of January the barometer has been abnormally high, and on the 18th January it attained a reading of 30.97 inches, which is the highest on record.
HISTORICAL HIGH BAROMETERS.
In looking back through the records of barometric readings, there are six occasions on which atmospheric pressures have been attained which approach closely to those recently recorded. These have been collected, and published in a letter in the Times of the 18th January, by Mr. G. J. Symons, F.R.S.
They are as below:
January, 1825 ...
There is one remarkable fact about the phenomena recorded in the above table, viz., that all these abnormally high pressures have occurred during the winter months.
* These readings are all corrected for temperature 32° F., and the sea level, except the first, and in the case of that observation it is not known whether these corrections have been applied.
The mean pressure in Great Britain is higher by about two-tenths of an inch in summer than in winter, but the highest readings seem always to occur in winter.
CYCLONIC (NORMAL) DISTURBANCES PRECEDING HIGH PRESSURE-ANTI-CYCLONIC DISTURBANCES ACCOMPANYING IT.
During the first week of January, 1882, the weather experienced in the British Isles was the normal winter weather. The atmospheric disturbances which passed over Great Britain came up as usual from the South of West, and passed away to the North of East. They were also cyclonic in form, i.e., the central area was one of low pressure, with isobars of higher pressure surrounding it, increasing as they extended outwards from the central area. The course of the
wind round the area of disturbance was also the true, or normal direction, being Westerly on the Southern side, and Easterly on the Northern side of the area.
During that time, however, an anti-cyclonic system of disturbance was forming in central Europe, and travelling up in a direction from S.E. to N.W.
The central area was one of high pressure, and the isobars surrounding it represented barometric readings decreasing as they receded from the central area of high pressure. The wind also circulated round in this system of disturbance in the opposite direction to that which it takes when the central area is one of low pressure; i.e., the wind was Easterly on the Southern side, and Westerly on the Northern side of this anti-cyclonic disturbance.
By the aid of twelve diagrams (copies of the Synchronous Weather Charts of Western Europe, showing the isobaric lines, wind direction and force, etc., at six p.m., which are published daily in the Times), the isobaric lines, and corresponding wind directions on twelve days between the 9th and 23rd of January, were shown.
It was thus pointed out that on the 9th of January normal cyclonic atmospheric disturbances prevailed over Western Europe, the N. W edge of the anti-cyclone being at the same time observed impinging on the Southern portion of the cyclonic movement. At this time the centre of the anti-cyclonic movement was over the Western part of Germany.
On the 11th January, the anti-cyclonic movement was spreading to the Northward, with its central area nearly stationary. The curves of the isobaric lines were deflected on the N.E side, owing to the proximity of a cyclonic disturbance, the centre of which was over the Gulf of Bothnia, and on the Western side, owing to another cyclonic disturbance making up to the Westward of Ireland.
From the 11th to 16th January the central area of high pressure remained nearly stationary over Northern Germany, the N.E. of France, and Belgium. The curves of the isobaric lines in the west of Ireland were on some occasions slightly deflected, marking the impingement of cyclonic disturbances travelling up from the S.Wa
On the 17th, the central area of high pressure was over the North of France, and was progressing slowly Westward; and on the 18th it was over the South of England, the highest readings having been attained on this day.
From the 19th to the 22nd, the central area of high pressure remained nearly stationary, though the barometer was falling steadily.
At six p.m. on the 20th, the reading was 30.7 inches, and on the 22nd it was 30.5 inches in the area of highest pressure, which still remained stationary over the South of England.
WEATHER DURING THE CONTINUANCE OF HIGH PRESSURE.
The weather over the whole of Western Europe during
this period was very settled; the winds were light, and blowing very steadily in the anti-cyclonic direction, the whole system seeming to stand like a stationary mass, against the western side of which cyclonic systems of unsettled weather working up from the South-westward impinged occasionally, and passed away to the Northward, skirting its Northwestern edge.
The weather in England, generally speaking, during the same period was dull, damp, and foggy, but without rain.
NOTE ON OBSERVATIONS SUBSEQUENT TO THE READING OF THE PAPER.
The above remarks brought the history of this abnormal weather up to the date on which the paper was read. As similar weather continued for some weeks afterwards, making the event even more noteworthy, the subjoined notes are added.
On the 22nd January, the barometer was falling slightly, and after falling to 30.5 inches, it commenced to rise again on the 23rd, and continued to read above 30.5 inches till the 28th January; during all this time the character of the atmospheric movements being distinctly anti-cyclonic. On the 29th and 30th, a cyclonic disturbance occupied the Northern portion of Western Europe, the anti-cyclonic movement still prevailing over the Southern portion of the area of observation. There was a threatening of bad weather, though none was experienced. These changes had been accompanied by a slight fall of pressure, but on the 31st the barometer rose again, and continued high, the weather being moderate and fine until the 12th and 13th February, on which days a cyclonic disturbance, accompanied by a gale of short duration, and a temporary diminution of pressure, passed over the north of Ireland, and Scotland. On the 14th of February the barometer was again rising, and con